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Firefox OS 1.1 Simulator4.0.4.1-signed

Firefox OS Simulator is a test environment for Firefox OS. Use it to test your apps in a Firefox OS-like environment that looks and feels like a mobile phone. After installing it, go to Web Developer > Firefox OS Simulator to access its features.

About this Add-on

Important! This add-on is compatible with Firefox 37+ and Firefox OS 1.1. To test apps with Firefox OS 1.2+, please use WebIDE built into Firefox! For more info, see the WebIDE MDN documentation.

This add-on is large (50-70MB), because it bundles a complete simulation of Firefox OS, including its default apps. So it takes multiple seconds for Firefox to install the add-on. Sometimes it takes so long that Firefox's Unresponsive Script dialog appears. If that happens, press the Continue button to let Firefox continue installing the add-on. It will eventually succeed.

Unstable preview builds of the next version of the addon are available. If you're comfortable using incomplete software, and you're interested in seeing new features in development or are having trouble using the stable release, then try installing the latest preview build for Windows, Mac, and Linux.